Method and means for making sequential drawings



l 1 R. .1. H. PLANIOL 2,295,754

METHOD AND MEANS FOR MAKING SEQUENTIAL DRAWINGS Filed Feb. 27, 1941 g- ATTORNEYS Patented Sept. 15, 1942 METHOD AND MEANS FOR MAKING SEQUENTIAL DRAWINGS Ren J. H. Planiol, New York, N. Y.

Application February 27, 1941, Serial No. 380,866

13 Claims.

My present invention relates to a method of making drawings, more particularly a series of drawings, and to apparatus adapted to carry out the method. The invention is particularly adapted for use in the production of so-called animated cartoons to eliminate much of the laborious work now required to be done by hand by the artist in depicting successive positions of characters of the cartoon drawing.

By the present invention, if two drawings are made of the same character but in different poses, a plurality of pictures or drawings corresponding to the intermediate positions assumed by the character in changing from the pose of one of the original drawings to that of the other, can be produced automatically, either directly on paper or better, on a photographic film. In order that the intermediate drawings or pictures be substantially accurate, the difference between the original drawings must not be too great. I have found that the accuracy of the intermediate drawings is high when the angular shift between homologous lines of the original drawings is 45 or less.

The permissible angular shift will depend, of course, upon the particular use to which the drawings or pictures are to be put, some uses requiring greater accuracy and others permitting or even preferring greater distortion.

For an understanding of how the additional drawings or pictures of a sequence may be obtained automatically in accordance with the invention, reference may be had to the accompanying drawing of which:

Fig. 1 represents a sequence of five drawings of which the first and last are the original drawings and the rest are produced automatically in accordance with the invention;

Fig. 2 is a sequence of seven drawings of a conventional form which illustrates the application of the invention to the making of intermediate drawings when the original drawings not only difier in pose or angular position but also in size and in thickness of homologous lines;

Fig. 3 is a plan view of an apparatus suitable for practicing the invention;

Fig. 4 is a vertical sectional view of the apparatus of Fig. 3, taken along the line 44 of Fig. 3;

Fig. 5 is an enlarged sectional view of one aperture controlling means of the apparatus of Figs. 3 and 4;

Fig 6 is a vertical sectional view of a modified form of apparatus suitable for practicing the invention, and

Fig. 7 is a plan View of a further modification of the invention.

The theory of the invention can best be understood by reference to Fig. 1. In Fig. 1 a sequence of five drawings or pictures I, 2, 3, 4 and 5 is shown, of which pictures I and 5 may be called originals. Each drawing represents an outline drawing of the same figure in a slightly different pose. Each point on drawing l corresponds to a point on drawing 5. For example A1 on drawing I and A5 on drawing 5 are corresponding or homologous points, each being at the tip of the left shoulder of the figure. Similarly, B1 and B5, C1 and C5 are pairs of homologous points. If now an elastic or other tensioned means is stretched between say A1 and A5, and the two ends of the elastic are made to trace the outline of the figures I and 5 in synchronism, that is, if one end of the elastic is moved from A1 to B1 simultaneously with the movement of the other end of the elastic from A5 to B5, and the tracing similarly continued around the figures, then fixed points along the elastic trace the intermediate drawings, 2, 3 and 4. This result is equally true, whether the original drawings are of the same or different size.

This is illustrated inFig. 2, where, for simplicity, the drawings or pictures are indicated as squares. In this case the original drawings 6 and I2 are of difierent size, drawing 12 being smaller than drawing 6 and being rotated through as compared to drawing 6. If the homologous sides of the squares 6 and I2 are traced synchronously, as above described in con nection with Fig. 1, points on an elastic stretched between the tracingpoints will trace the intermediate squares I, 8, 9, l0 and II. As shown, squares 1, 8, 9, l0 and H diminish in size and change sequentially in angular position.

Various mechanisms for obtaining the intermediate drawings of a sequence will now be described.

In Figs. 3 and 4, I3 represents any suitable table or support, upon which is a strip of light sensitive material M, as for example, a sensitive photographic film, covered by a protective transparent sheet iii of any suitable material. Above the sheet I6 is an opaque elastic sheet l8 which is secured at each end to a rigid plate 20 of transparent material, as for example of glass or of a suitable plastic. Springs 22, each secured at one end to a fixed post 24 and at the other end to a plate 20, serve as counterweights for the tension of the elastic sheet I8. Other means for this purpose could be provided, as for example weights supported by pulleys or by a suitable system of levers. The original drawings are positioned beneath plates 26 so as to be traceable by tracer points 26 and 27, respectively, rotatably mounted in apertures in the plates 20. The elastic sheet I8 is provided with a number of spaced apertures 28, corresponding with the number of intermediate drawings of the sequence to be made.

In the particular embodiment of the invention illustrated in Figs. 3, 4 and 5 each aperture 23 is controllable in size and comprises a small iris diaphragm mounted on an eyelet 29 (see Fig. 5) set in the sheet l8 and adjustable by means of elastic cords 30 passing around pulleys 3| mounted on the movable leaves of the diaphragm. A cord 30 passes around a pulley 32 rigidly mounted on tracer pencil 26 and another cord 30 passes around a pulley 33 rigidly mounted on tracer pencil 21. fected of the width of the lines of the intermediate drawings, as rotation of the tracer pencils varies the openings of the iris diaphragm by rotation of the pulleys 32 and 3!. Suitable graduations 34 on the plates 20, cooperating with an index 35 on the tracers 26 and 21 are provided for indicating the proper angular rotation for any width of line desired. When both indices 35 are set in the same position the lines of all the drawings will be of equal width, as for example in Fig. 1 or as in the sides of the squares of Fig. 2. Where the width of homologous lines of the original drawings is different, as in the case of the diagonals of the squares of Fig. 2, the indices on the tracers 26 and 21 are set differently, each corresponding to the width of the line of the drawing being traced. The result, due to elasticity of the cords 30 and the diiferential effect of the settings of tracers 25 and 21, is the gradual change in width of the homologous lines of the intermediate drawings, as shown by the decreas ing width of the diagonals of drawings 1, 8, 9, l0 and H of Fig. 2. Suitable lights L are provided above the sheet I8 and a suitable protective housing 36 shields the aperture against an traneous light.

To operate the above described apparatus, the operator at one end of the table first sets the tracer 26 on a point of one original drawing while the operator at the other end of the table sets the tracer 21 on the homologous point of the other original drawing. The indices 35 are then set for the desired width of line, and lights L are illuminated. The two operators then synchronously trace the original drawings always keeping the tracers on homologous points and without rotation of the plates 20. With a little practice and particularly by the use of definite time signals, the operators are easily able to synchronize the tracings. While the original drawings are being traced, the light passing through the apertures 26, on to the sensitive surface l4 traces the outlines of the intermediate drawings. Upon development, the resultin pictures are obtained.

Where more complicated drawings are to be made and it is necessary to move the tracers 26 and 21 from one line to another of the drawings, it is only necessary to extinguish the light L during realignment of the tracers.

The width of the sheet it should be at least twice the height of the picture to be drawn to prevent exposure of the sensitive film during the tracing movement. Also. to prevent overlapping of the intermediate drawings, the apertures should be spaced sufiiciently far apart. If W is the width of one drawing and L the length be- With this arrangement control is eftween a pair of homologous points of the original drawings, then the number of intermediate drawings, N, must be less than if overlapping is to be avoided.

With the above described apparatus of Figs. 3, 4 and 5 the intermediate drawings are made to the same scale as the original drawings. If enlargements or reductions are desired, the apparatus of Fig. 6 may be conveniently employed. In this construction, the apertures 28 in the sheet i 8 are omitted and light diffusing or reflecting points, 2.8 are substituted therefor. Above each point 28 is positioned a suitable lens system 31 which is supported in a suitable housing structure 38. A photographic plate 39 is positioned within the housing 38, conveniently on a door 43, above each lens system 31. Each lens system is focused to cover the field of the drawing to be traced by the diffusing point 28. With this arrangement the intermediate drawings may be produced if desired in diiferent scales and in scales different from that of the original drawings. Also, by painting the table and elastic sheet IS a non-reflecting black, a relatively narrow sheet may be used.

If control of width of line as well a enlargement of intermediate drawings is desired, the above described iris diaphragm 28 and the control thereof from the tracers 26 and 21 could be positioned above the diffusers 28 or could be substituted for such diffusers, in which latter case, of course, the lamp L would be suitably positioned beneath the sheet [8.

Instead of producing the intermediate drawings photographically, they may be obtained directly by the use of pencils or other markers. For example, an apparatus of the type disclosed in Fig. 7 may be employed in which the sheet I8 is replaced by a structure comprising a pair of similar springs 42 extending longitudinally along the table and joined by rigid cross members 44 corresponding in number to the number of intermediate pictures to be drawn. The ends of the spring 42 are secured to the rigid transparent sheets 23 carrying the pointers 26 and 21. Each cross bar 44 is apertured, as at 45, through which a pencil may be inserted and by which the pencil may be held in any suitable manner. When the pointers 26 and 21 are passed synchronously around drawings therebeneath, pencils in the apertures 45 will trace the intermediate drawings on a sheet of paper 46 placed on the table for engagement. with the pencils. A small amount of friction will be introduced by the use of penoils in the apparatus of Fig. 7, but by proper adjustment of the pencils, the errors of distortion introduced by such friction may be made practically negligible.

Various embodiments of the invention have now been described in connection with the drawings. It will be apparent from the above description that the invention, in its broadest aspect, comprises the synchronous tracing of two drawings of a sequence to obtain automatically additional drawings of the sequence. The original drawings must not be too far removed in sequence, if high accuracy of the additional drawings is desired. Mathematical computations to show the resultant accuracy are complicated and need not be discussed herein but certain principles may be stated. Take, for example, a simple sequence of rotated squares where the original squares are of the same size. If the homologous sides of the two original squares make an angle of 30 with each other, the corners of the intermediate drawings Will be substantailly 90 and the scale of the drawings will be substantially the same as that of the original drawings. When the homologous sides are at an angle of 45 the corners of the intermediate figures will be within 1 of 90 and the length of any side of the intermediate drawings will differ from the length of the sides of the original squares by not more than When the homologous sides of the original squares are at right angles to each other, the angular distortion of the intermediate drawings increases and the dimensional distortion increases to 30%. Thus for reasonably accurate production of sequential drawings the angular displacement between homologous parts of the original drawings should not be more than 45, but if comic or distorted effects are desired, greater angular displacement is allowable. A comic series, for example, can be obtained when the original drawings correspond to inverted figures. That is, suppose one drawing is of a man standing on his feet and the other of the same man on his head. The intermediate series for such drawings will consist in a series of shorter and shorter upright men vanishing to a dot halfway between the original drawings and followed by a series of taller and taller men standing on their heads. Other comic effects obtainable by the invention are readily apparent. For example a sequential transformation from a man to an animal or vice versa, or from a piece of furniture to a man, etc. In these cases, distortion of the intermediate drawings is of no importance, in fact is meaningless.

Although the invention has been described as applied to the production of drawings intermediate two original drawings of a sequence, clearly the same principles apply and similar apparatus could be employed if sequential drawings are desired that are not intermediate, but beyond the two original drawings. That is, if drawings 2 and 4 of Fig. l are the original drawings, then synchronous tracing of these drawings will produce not only the intermediate drawing 3 but also the additional drawings I and 5 of the sequence, it being only necessary for this purpose to extend the elastic means connecting the tracers.

In the above description of the invention with reference to both the method and the apparatus I have indicated that two operators will trace the original drawings simultaneously. Suitable mechanical linkages, however, could be provided so that one operator, with the help of mirrors, could manipulate the apparatus, or entirely mechanical means for the synchronous tracing of the drawings could be devised for practicing the method of the invention.

I claim:

1. The method of producing sequential drawings which comprises synchronously tracing homologous lines of a pair of original drawings of a sequence with interconnected tracing means to determine the locus of a point bearing a fixed ratio to homologous points of the original drawings, and simultaneously recording such locus as an additional drawing of the sequence.

2. The method of producing an additional drawing of a sequence from two original drawings which comprises synchronously tracing homologous lines of the original drawings by elastically connected tracing means to cause a part of the elastic connection to travel concurrently about a path corresponding to the intermediate drawing to be obtained and simultaneously recording said path traversed by the said part of the elastic connection.

3. A method of producing additional drawings of a sequence from two original drawings of the sequence which comprises stretching an elastic member between homologous points of the original drawings, passing light through apertures in the elastic member on to a light sensitive surface while synchronously tracing the original drawings along homologous lines with tracers connected with the elastic member.

4. The method according to claim 3 including adjusting the size of the apertures to vary the width of the lines produced on the sensitive surface by the light passing through the moving apertures during the tracing of the original drawings.

5. A method of producing drawings intermediate two original drawings of a sequence which comprises connecting an elastic member between homologous points of the original drawings, optically magnifying the paths traversed by points on the elastic member during synchronous tracing of the original drawings along homologous lines by tracers connected with the elastic member and simultaneously photographically recording said magnified paths,

6. A mechanism for making sequential drawings from two original drawings of a sequence which comprises a tracer for each original drawing, means elastically connecting said tracers under tension, means for counterbalancing the tension of said connecting means, and means for reproducing the paths traversed by separated points on said connecting means, whereby when said original drawings are synchronously traced along homologous lines, said reproducing means produce homologous lines of additional drawings of the sequence.

'7. A mechanism according to claim 6 wherein said connecting means comprises an opaque elastic sheet and wherein said reproducing means comprises a light sensitive surface cooperating with apertures in said elastic sheet for photographically reproducing the paths of the aper tures during synchronous tracing of the original drawings.

8. A mechanism according to claim 6 wherein said connecting means include spring members and wherein said reproducing means comprises markers carried by said connecting means and a material having a markable surface engaged by said markers during tracing of the original drawings.

9. A mechanism according to claim 6 wherein said reproducing means includes optical systems for varying the size of the intermediate drawings relative to the size of the original drawings.

10. A mechanism for making additional drawings of a sequence from two original drawings of the sequence comprising in combination means for tracing each original drawing, elastic means connecting said tracing means, said elastic means being provided with a number of apertures, a light sensitive material positioned to receive light passing through said apertures and means for controlling the size of said apertures to control the width of the light path traced on said sensitive material when the original drawings are traced.

11. A mechanism according to claim 10 wherein said aperture controlling means comprises means associated with each tracing means and operative for conjoint control of the apertures whereby the size of the apertures may be varied sequentially or made equal as desired.

12. A mechanism for making additional drawings of a sequence from two original drawings of the sequence which comprises a tracing means for each original drawing, an elastic connection of non-light reflecting material connecting said tracing means, reflecting spots on the surface of said elastic connection, light sensitive material positioned above said reflecting spots and means for focusing light reflected from said spots upon said light sensitive material whereby when said original drawings are synchronously traced by said tracing means along homologous lines, homologous lines of additional drawings of the sequence are produced on said light sensitive material,

13. A mechanism for making additional drawings of a sequence from two original drawings of the sequence comprising in combination a pair of rigid transparent sheets, tracing means carried by each of said sheets, elastic means connecting said sheets under tension, means connected with said sheets for counterbalancing the tension of said connecting means, and means for reproducing the paths traversed by separated points on said connecting means, whereby when said original drawings are positioned beneath said sheets and homologous lines thereof are synchronously traced by said tracing means said reproducing means produce homologous lines of additional drawings of the sequence.

RENE J. H. PLANIOL. 

